Iron Biogeochemistry in the Northern Barents Sea: Seasonal Variability in Distribution and Concentration in a Changing Arctic Ecosystem

Nicolas Sanchez, Norwegian University of Science and Technology (NTNU), Chemistry, Trondheim, Norway and Murat V Ardelan, Norwegian University of Science & Technology (NTNU), Trondheim, Norway
Abstract:
The Arctic ecosystem is one of the most vulnerable regions to the effects of Climate Change. Yet, certain areas remain as one of the least studied, particularly where the seasonal variability in key processes is the least known of all. Decline in the ice extent, ocean acidification, together with the freshwater discharge from glaciers are among the most relevant factors affecting the overall biogeochemistry of trace metals in the water column and sea ice. This has a direct effect on the primary production and therefore the overall pelagic ecosystem.

As part of the Nansen Legacy project, seasonal cruises are and will be conducted during 2018-2019-2020 on a ~1000 km transect along the east coast of the Svalbard archipelago, over the shallow continental shelf, then penetrating into the Nansen Basin. Collection of trace metal samples are conducted on seven oceanographic stations and occasionally from sea ice by trace metal clean techniques, preconcentrated by seaFAST and analyzed by -HR-ICPMS.

The project will constitute a basis to study the spatial and seasonal variability regarding the distribution of iron and other bio essential elements in the region. Increased light penetration and nutrient availability are variables highly linked to the seasonal ice extent. In this case, the seasonal coverage will allow to study this coupling and the links to primary production and early blooms in areas where only summer data is available. The coverage of more than one year in certain seasons, will generate knowledge on the variability on trace metal concentration and distribution in connection with processes such the Atlantic water input and sea ice extent.